Newborn Metabolic Screening Programme Annual Report January to December 2014
Copyright The copyright owner of this publication is the Ministry of Health, which is part of the New Zealand Crown. The Ministry of Health permits the reproduction of material from this publication without prior notification, provided that all the following conditions are met: the content is not distorted or changed the information is not sold the material is not used to promote or endorse any product or service the material is not used in an inappropriate or misleading context having regard to the nature of the material any relevant disclaimers, qualifications or caveats included in the publication are reproduced the New Zealand Ministry of Health is acknowledged as the source. Disclaimer This publication reports on information provided to the Ministry of Health by Auckland District Health Board. The purpose of this publication is to inform discussion and assist ongoing NMSP development. All care has been taken in the production of this report, and the data was deemed to be accurate at the time of publication. However, the data may be subject to slight changes over time as further information is received. Before quoting or using this information, it is advisable to check the current status with the Ministry of Health. Acknowledgements We would like to thank all those people involved in producing this report. We would particularly like to acknowledge those who have collected this information, those who have entered the data, and those who have facilitated the analysis of the data. In particular ADHB staff; Dianne Webster, Joan Carll, and Keith Shore; and the paediatricians who provide the information about the diagnoses in screen positive babies. Citation: Ministry of Health. 2014. Newborn Metabolic Screening Programme Annual Report 2014. Wellington: Ministry of Health. Published in April 2016 by the Ministry of Health PO Box 5013, Wellington 6145, New Zealand ISBN 978-0-478-42840-7 (online) HP 5914 This document is available at www.nsu.govt.nz
Contents Executive summary... iv Introduction... 1 Background to the Newborn Metabolic Screening Programme... 1 The aim of the Newborn Metabolic Screening Programme... 2 Data included in this report... 2 National monitoring indicators... 3 Indicator 1: Screening coverage... 4 Indicator 2: Timing of sample taking... 6 Indicator 3: Quality of blood samples... 11 Indicator 4: Sample dispatch and delivery... 13 Indicator 5: Laboratory testing timeframes... 15 Indicator 6: Timeliness of reporting notification of screen positives... 16 Indicator 7: Collection and receipt of second samples... 18 Indicator 8: Diagnosis and commencement of treatment by disorder... 19 Indicator 9: Blood spot card storage and return... 21 Screening performance and incidence... 22 Follow-up of positive tests... 22 Clinical utility... 23 Incidence of screened disorders... 24 Appendix 1: NMSP National Indicators... 25 Newborn Metabolic Screening Programme ii
Abbreviations CAH CF CH FAOD GP HIPC LMC MCAD MSUD NICU NMSP NSU PKU SCBU Congenital Adrenal Hyperplasia Cystic Fibrosis Congenital Hypothyroidism Fatty Acid Oxidation Disorder General Practitioner Health Information Privacy Code Lead Maternity Carer Medium Chain Acyl-CoA Dehydrogenase Maple Syrup Urine Disease Neonatal Intensive Care Unit Newborn Metabolic Screening Programme National Screening Unit Phenylketonuria Special Care Baby Unit Newborn Metabolic Screening Programme iii
Executive summary Almost all babies born in New Zealand have been screened since the Newborn Metabolic Screening Programme (NMSP) began in 1969, and as a result, over 45 babies are identified with and treated for a metabolic disorder each year. When a baby is diagnosed with a metabolic disorder in early infancy, treatment can commence immediately, preventing life-threatening illness and limiting the impact on the baby s development potential. Key points for January to December 2014 58,673 babies were tested and 59,097 born, giving a screening coverage of 99%. 74% of samples were collected within the 48-72 hour timeframe. No DHB and no ethnic group met the standard of 95% within the timeframe. Babies of lower NZDep and European ethnicity are more likely to have the sample collected within the appropriate timeframe. Overall 98% of samples were suitable for testing. One DHB met the standard of 99% of samples suitable. The main reasons samples were unsuitable were taken too early or not sufficient/contaminated sample card. Follow-up of unsuitable samples was 92%. 66% of samples were received by the laboratory in four days or less. No DHB met the standard of 95% within four days. The laboratory testing timeframes standard of 100% was met for galactosemia and biotinidase deficiency screening and was 99% for the other disorders. Of 33 clinical critical results, 31 were notified within the timeframe, the remaining two were two days late. Although only 38% of second samples were received in ten days or less (the standard is 100%), 97% of follow-up was completed appropriately. Treatment was commenced by the specified age for 40% of babies with diagnosed disorders, for however most of the remainder were just outside the range, except for one patient with PKU treated at 25 days and one with MCAD at 50 days (both due to delayed transit time of the sample to the laboratory). There were no known clinical ill-effects from the delays. 99% of 666 requests for card returns were made in 28 days or less (the standard is 100%). 76 cards were used for additional testing for family health reasons, mostly for CMV testing. 150 cards were used for research in one study. Follow-up of positive tests was between 94-100%. All clinical critical results had appropriate follow-up. 60 cases of screened disorders were detected by the programme and in 52 of these there was no clinical suspicion of the disorder before the screening test result. Newborn Metabolic Screening Programme iv
Introduction The purpose of this annual report is to provide information on the performance of the NMSP against the agreed set of national indicators. Regular analysis of data against programme indicators is a key monitoring and evaluation tool of the NMSP. Reports are published on the National Screening Unit (NSU) website. This is the fourth annual report of the NMSP following the development of national indicators and completion of the NMSP Monitoring Framework in November 2010. Appendix 1 outlines the NMSP standards and indicators. Further information on the NMSP Monitoring Framework can be found at: www.nsu.govt.nz/files/nsu_screening_programme_2_0.pdf Background to the Newborn Metabolic Screening Programme Newborn babies in New Zealand have been screened for congenital metabolic disorders in a national screening programme since 1969. New Zealand was one of the first countries in the world (with Ireland), to have a national screening programme. The National Testing Centre (the laboratory arm of the programme) was established by the late Professor Arthur Veale working with the late Professor Bob Guthrie in the Human Genetics Research Unit at the School of Medicine in Dunedin. The laboratory moved to Auckland in 1973 when Professor Veale became the foundation professor of Community Health and Human Genetics in what was then the new medical school. Since 2005, the NMSP has been overseen nationally by the National Screening Unit of the Ministry of Health. Significant milestones for the programme include the introduction of expanded newborn screening (adding fatty acid oxidation and more amino acid breakdown disorders) in 2006. In 2009 educational and training resources (DVDs and videos) about newborn screening and best practice for lead maternity carers (LMCs) were produced and distributed. Post-paid envelopes and lancets are now supplied to LMCs. Parent information sheets about congenital hypothyroidism, cystic fibrosis and MCAD and a general sheet about autosomal recessive inheritance have been developed for use in the diagnostic process. Almost all babies born in New Zealand have been screened since the NMSP began and over 45 babies are identified with and treated for a metabolic disorder each year. When a baby is diagnosed with a metabolic disorder in early infancy, treatment can commence immediately, preventing life-threatening illness and limiting the impact on the baby s development potential. Newborn metabolic screening involves collecting blood samples from babies heels (the heel prick test ) onto a blood spot card (a Guthrie card ). Blood samples must be collected between 48 and 72 hours of baby s age for maximum utility. The blood samples are screened for over 20 metabolic disorders. The NMSP is monitored and evaluated by the NSU to ensure it continuously meets high standards. A multi-disciplinary advisory group provides expert leadership and advice for the Newborn Metabolic Screening Programme 1
programme. The NMSP Technical Group reviews monitoring reports and makes recommendations. The aim of the Newborn Metabolic Screening Programme The aim of the NMSP is to reduce morbidity and mortality through high-quality screening that facilitates early detection and treatment of specific metabolic disorders in pre-symptomatic babies. The objectives of the programme are to: enable early detection of pre-symptomatic newborns ensure appropriate early referral to treatment of newborns ensure babies born with congenital metabolic disorders have their development potential impacted as little as possible from the disorder facilitate continuous monitoring of specific metabolic disorders maintain high uptake of screening, community participation and trust facilitate continuous quality improvement through the development of quality assurance, reporting, education and the strategic planning framework inform the community of all aspects of newborn screening including the storage and use of blood spot cards. Data included in this report Screening data is obtained from the LabPLUS Delphic laboratory information system (Delphic). The extracted data is then placed in a temporary table on the Delphic Data Warehouse and imported into a MS Access database for analysis. Data on DHB, ethnicity and NZ Deprivation Index (NZDep) is obtained from the Ministry of Health National Collections and merged with the LabPLUS data based on each individual s national health index (NHI). Samples selected for inclusion in this report are based on the date they are received at the laboratory. For this reporting period, only valid samples received from 1 January to 31 December 2014 are included. For coverage and timing, samples are only included if they are a first sample received from a baby. Follow-up samples are excluded, because if a baby is screened in one reporting period, and has follow-up in the next period, they would be counted twice or age at sampling would likely fall outside the standard. Ethnicity is based on the prioritised NHI ethnicity information. All reporting by NZDep is based on the extraction against the NHI associated with residential addresses. Decile 1 has the least deprivation and decile 10 the most deprivation. While many LMCs are not directly responsible to a particular DHB, data is reported by DHB region, as this is the most usual way of comparing health information across New Zealand. Timing of sample taking (Indicator 2) is now reported in hours unless the date and time of birth and sample collection are not provided. The improvement in the quality of data in 2012 to monitor this indicator is a significant achievement for the NMSP. Newborn Metabolic Screening Programme 2
National monitoring indicators Table 1 summarises the NMSP indicators used for regular monitoring with their reporting frequency and detail included in Appendix 2. These indicators have been developed following consultation with key NMSP stakeholders. Indicators will be further refined as data is collected over time, and will be subject to regular review by the NMSP Technical Group. Table 1 NMSP indicators Indicators Detail 1. Newborn Metabolic Screening Coverage DHB Ethnicity Deprivation status 2. Timing of sample taking DHB Ethnicity Deprivation status Laboratory reporting 3. Quality of Blood Samples DHB 4. Sample dispatch and delivery DHB 5. Laboratory testing timeframes 6. Timeliness of reporting - notification of screen positives 7. Collection and receipt of second samples DHB Incidence 8. Diagnosis and commencement of treatment by disorder: Biotinidase deficiency Cystic fibrosis Congenital hypothyroidism Congenital adrenal hyperplasia Galactosaemia Amino acid disorders Fatty acid oxidation disorders 9. Blood spot card storage and return Newborn Metabolic Screening Programme 3
Indicator 1: Screening coverage Overall samples were received from 58,673 newborns between January and December 2014. The number of newborns screened is determined by the number of unique NHI numbers for each DHB. Some instances of the same NHI number used for more than one infant in a DHB have been found which explains why the total of infants counted in this way is slightly less than when counted by other parameters. Data from National Maternity Collection of the Ministry of Health shows 59,097 babies were born in 2014. For screening, the numbers counted are babies screened within the calendar year. This might vary slightly from the number of babies in the calendar year. Approximately 99% of babies were screened. Denominator data is sourced from the National Maternity Collection. Table 2 outlines the numbers of babies screened and annual coverage from 2007 to 2014. Table 2 Number of babies screened and coverage 2007 2013 Year Births Babies Coverage % screened 2007 64,040 65,121 97.7 2008 65,333 63,794 97.6 2009 63,285 63,516 100.4 2010 64,699 63,727 98.5 2011 62,733 61,859 98.6 2012 62,842 61,422 97.7 2013 59,707 59,192 99.1 2014 59,097 58,673 99.3 Newborn Metabolic Screening Programme 4
Table 3 outlines babies screened by DHB. Coverage by DHB ranges from 96 to 107%, indicating a mismatch of DHB data between the Ministry of Health maternity data and the NHI data. As noted in previous reports there is no reliable screening denominator. Table 3 Number of babies screened by DHB, January to December 2014 DHB Region Births Babies screened Coverage % Northland 2,097 2,146 102.3 Waitemata 7,910 7,740 97.9 Auckland 6,370 6,148 96.5 Counties Manukau 8,279 8,096 97.8 Waikato 5,325 5,274 99.0 Lakes 1,393 1,394 100.1 Bay of Plenty 2,785 2,809 100.9 Tairawhiti 722 695 96.3 Taranaki 1,529 1,548 101.2 Hawkes Bay 2,098 2,123 101.2 Whanganui 822 811 98.7 Mid Central 2,112 2,090 99.0 Hutt Valley 1,863 1,859 99.8 Capital and Coast 3,572 3,418 95.7 Wairarapa 443 472 106.5 Nelson Marlborough 1,438 1,468 102.1 West Coast 353 369 104.5 Canterbury 6,032 5,933 98.4 South Canterbury 658 649 98.6 Southern 3,296 3,277 99.4 Not recorded* 354 Total 59,097 58,673 99.3 *does not include babies born to mothers who usually reside overseas Newborn Metabolic Screening Programme 5
Indicator 2: Timing of sample taking This indicator is monitored by the number of screens performed. In 2014, 58,747 babies had a screen and 58,944 screens were done. This includes 197 babies who had more than one screen. The standard for this indicator is 95% of first samples are taken between 48 and 72 hours after birth. No DHB met the standard of 95%. Table 4 identifies the percentage of samples taken by DHB. Nationally 74.1% of samples were collected at 48 to 72 hours, and 21.9% at greater than 72 hours. Table 4 Timing of sample taking by DHB, January to December 2014 DHB region Sampled at 48-72 hours Sampled less than 48 hours Sampled greater than 72 hours No collection date and/or date of birth Total number of screens* No. % No. % No. % No. % No. Northland 1,447 67.1 13 0.6 621 28.8 74 3.4 2,155 Waitemata 5,938 76.5 61 0.8 1,601 20.6 158 2.0 7,758 Auckland 5,093 82.5 53 0.9 810 13.1 217 3.5 6,173 Counties 5,247 64.6 54 0.7 2,382 29.3 437 5.4 8,120 Manukau Waikato 3,174 60.0 47 0.9 1,885 35.6 183 3.5 5,289 Lakes 981 70.2 14 1.0 357 25.5 46 3.3 1,398 Bay of Plenty 1,740 61.8 17 0.6 968 34.4 92 3.3 2,817 Tairawhiti 532 76.2 1 0.1 147 21.1 18 2.6 698 Taranaki 1,241 80.0 10 0.6 259 16.7 42 2.7 1,552 Hawkes Bay 1,681 78.7 11 0.5 401 18.8 42 2.0 2,135 Whanganui 563 69.2 8 1.0 221 27.2 21 2.6 813 Mid Central 1,607 76.6 14 0.7 407 19.4 70 3.3 2,098 Hutt Valley 1,280 68.4 5 0.3 535 28.6 51 2.7 1,871 Capital and Coast 2,731 79.5 17 0.5 602 17.5 85 2.5 3,435 Wairarapa 351 74.2 4 0.8 105 22.2 13 2.7 473 Nelson 1,192 80.8 14 0.9 227 15.4 42 2.8 1,475 Marlborough West Coast 307 83.2 3 0.8 45 12.2 14 3.8 369 Canterbury 5,271 88.6 34 0.6 494 8.3 149 2.5 5,948 South Canterbury 534 82.2 3 0.5 101 15.5 12 1.8 650 Southern 2,509 76.4 9 0.3 667 20.3 101 3.1 3,286 Not recorded 269 75.4 7 2.0 63 17.6 18 5.0 357 Total 43,688 74.2 399 0.7 12,898 21.9 1,885 3.2 58,870* *Total includes 197 babies who have had more than one screen Newborn Metabolic Screening Programme 6
Figure 1 outlines the percentage of samples taken at 48 to 72 hours and shows that in 2014 no DHB met the 95% standard. Figure 1 Percentage of samples taken at 48 to 72 hours, by DHB, January to December 2014 Newborn Metabolic Screening Programme 7
Table 5 shows detailed information by ethnicity. Māori (68%) and Pacific (66%) babies are less likely than European (77%) and Asian (78%) babies to have a sample collected at two days. It is noted that the 95% standard was not met by any ethnic group. Table 5 Timing of sample taking by Group 1 and Group 2 ethnicity, January to December 2014 Ethnicity (Group 1 Group 2) Sampled at 48-72 hours Sampled less than 48 hours Sampled greater than 72 hours No collection date and/or date of birth Total number of screens* No. % No. % No. % No. % No. Māori 8,580 68.3 93 0.7 3,470 27.6 428 3.4 12,571 Pacific 3,933 65.9 48 0.8 1,725 28.9 262 4.4 5,968 Cook Island 617 66.1 2 0.2 271 29.0 44 4.7 934 Māori Fijian 322 68.4 0 0.0 128 27.2 21 4.5 471 Niuean 212 64.8 4 1.2 99 30.3 12 3.7 327 Samoan 1,577 65.7 25 1.0 698 29.1 100 4.2 2,400 Tokelauan 77 70.0 1 0.9 27 24.5 5 4.5 110 Tongan 919 65.2 13 0.9 415 29.4 63 4.5 1,410 Other Pacific 209 66.1 3 0.9 87 27.5 17 5.4 316 Asian 7,262 77.9 66 0.7 1,683 18.1 306 3.3 9,317 Chinese 2,925 82.0 17 0.5 540 15.1 83 2.3 3,565 Indian 2,079 73.3 27 1.0 604 21.3 128 4.5 2,838 Southeast Asian 827 77.8 8 0.8 199 18.7 29 2.7 1,063 Other Asian 1,431 77.3 14 0.8 340 18.4 66 3.6 1,851 European 23,106 77.2 182 0.6 5,793 19.4 854 2.9 29,935 NZ European 19,682 77.1 153 0.6 4,958 19.4 743 2.9 25,536 Latin American / 265 78.9 2 0.6 62 18.5 7 2.1 336 Hispanic Other European 3,159 77.8 27 0.7 773 19.0 104 2.6 4,063 Other 808 70.1 10 0.9 227 19.7 108 9.4 1,153 African 272 76.8 3 0.8 72 20.3 7 2.0 354 Middle Eastern 333 73.5 4 0.9 104 23.0 12 2.6 453 Other/not known 202 74.3 3 1.1 51 29.8 16 5.9 272 Total 43,688 74.2 399 0.7 12,898 21.9 1,885 3.2 58,870* *Includes 197 babies who had more than one first screen Newborn Metabolic Screening Programme 8
Figure 2 outlines the percentage of samples taken at 48 to 72 hours by ethnicity. In 2014 the standard of 95% was not met for any ethnic group. Figure 2 Percentage of samples taken at 48 to 72 hours, by ethnicity, January to December 2014 Table 6 shows the number of samples taken at two days by NZDep. The data indicates a slightly lower percentage of samples taken by the recommended time for babies in the five groups with the highest levels of deprivation (NZDep 6 to 10). Table 6 Percentage of samples taken at 48 to 72 hours by NZDep, January to December 2014 NZDep Sampled at 48-72 hours Sampled less than 48 hours Sampled greater than 72 hours No collection date and/or date of birth Total number of screens* No. % No. % No. % No. % No. 1 3,131 79.6 19 0.5 690 17.5 92 2.3 3,932 2 3,718 78.6 30 0.6 836 17.7 146 3.1 4,730 3 3,689 79.2 28 0.6 833 17.9 109 2.3 4,659 4 3,562 79.2 35 0.8 769 17.1 131 2.9 4,497 5 4,110 77.1 31 0.6 1,035 19.4 158 3.0 5,334 6 4,266 75.6 39 0.7 1,177 20.9 159 2.8 5,641 7 4,713 74.2 45 0.7 1,402 22.1 193 3.0 6,353 8 5,341 72.3 45 0.6 1,757 23.8 242 3.3 7,385 9 5,379 70.0 55 0.7 1,945 25.3 300 3.9 7,679 10 5,508 66.4 65 0.8 2,391 28.8 337 4.1 8,301 Not 271 75.5 7 1.9 63 17.5 18 5.0 359 recorded Total 43,688 74.2 399 0.7 12,898 21.9 1,885 3.2 58,870* *Includes 197 babies who had more than one first screen Newborn Metabolic Screening Programme 9
Figure 3 identifies the percentage of samples taken at 48 to 72 hours by NZDep. In 2014 no New Zealand deprivation level decile reached the 95% target. Figure 3 Percentage of samples taken at two days, by NZDep, January to December 2013 Newborn Metabolic Screening Programme 10
Indicator 3: Quality of blood samples Accurate testing of blood spot samples is reliant on the quality of the blood spot sample. Unsatisfactory samples require a repeat sample which could have been avoided. Table 7 shows that only one DHB met or exceeded the standard of 99% of blood spot samples suitable for testing. Table 7 Percentage of blood samples that meet quality standards by DHB, January to December 2014 DHB region Satisfactory Unsatisfactory Total samples No. % No. % No. Northland 2,115 98.1 40 1.9 2,155 Waitemata 7,619 98.2 139 1.8 7,758 Auckland 6,090 98.7 83 1.3 6,173 Counties Manukau 7,934 97.7 186 2.3 8,120 Waikato 5,211 98.5 78 1.5 5,289 Lakes 1,361 97.4 37 2.6 1,398 Bay of Plenty 2,782 98.8 35 1.2 2,817 Tairawhiti 686 98.3 12 1.7 698 Taranaki 1,528 98.5 24 1.5 1,552 Hawkes Bay 2,098 98.3 37 1.7 2,135 Whanganui 796 97.9 17 2.1 813 Mid Central 2,054 97.9 44 2.1 2,098 Capital & Coast 1,837 98.2 34 1.8 1,871 Hutt Valley 3,371 98.1 64 1.9 3,435 Wairarapa 470 99.4 3 0.6 473 Nelson Marlborough 1,452 98.4 23 1.6 1,475 West Coast 365 98.9 4 1.1 369 Canterbury 5,878 98.8 70 1.2 5,948 South Canterbury 643 98.9 7 1.1 650 Southern 3,238 98.5 48 1.5 3,286 Not recorded 83 96.5 3 3.5 86 Total 57,875 98.3 995 1.7 58,870 *197 babies have two first samples. Figure 4 outlines the reasons why samples were unsatisfactory. These included: 219 samples were collected too early (before 48 hours of age) 675 had a problem with the blood collection (such as insufficient blood, no demographics on the card or the sample was contaminated) 140 either took longer than one month, flap folded onto wet blood causing significant loss onto the flap, were damaged in transit or put wet into a plastic bag. Newborn Metabolic Screening Programme 11
Second samples were requested from 1034 babies and received from 950 (91.9%). The request was declined by 42 families (4.1%); nine babies died (0.9%) and the remaining 33 (3.2%) were lost to follow-up. Figure 4 Reasons for unsatisfactory samples, January to December 2014 Newborn Metabolic Screening Programme 12
Indicator 4: Sample dispatch and delivery The NMSP relies on timeliness of sample dispatch and delivery. The standard is for 95% of samples are received by the laboratory within four calendar days of being taken. Table 8 shows that nationally 65.6% of samples were received within four days, and 34.4% received after four days. The range received in four days or less was 46.7 to 79.2%. Although postage paid envelopes have been supplied to specimen submitters and this greatly improved transit times across all DHBs, no DHB met the standard of 95%. Overall, fewer samples were received in time in 2014 compared to 2013 and this may be associated with a reduction in box clearance times by NZ Post. Table 8 Percentage of samples received by the laboratory within four days by DHB, January to December 2014 DHB region Less than or equal to 4 days Greater than 4 days Unknown Total samples No. % No. % No. % No. Northland 1,422 66.0 732 34.0 31 1.4 2,154 Waitemata 5,277 68.1 2,477 31.9 61 0.8 7,754 Auckland 3,965 64.3 2,200 35.7 74 1.2 6,165 Counties Manukau 5,215 64.3 2,894 35.7 133 1.6 8,109 Waikato 3,612 68.4 1,665 31.6 66 1.3 5,277 Lakes 1,012 72.5 383 27.5 26 1.9 1,395 Bay of Plenty 1,916 68.1 898 31.9 40 1.4 2,814 Tairawhiti 436 62.5 262 37.5 8 1.1 698 Taranaki 1,083 69.9 466 30.1 18 1.2 1,549 Hawkes Bay 1,037 48.7 1,094 51.3 19 0.9 2,131 Mid Central 644 79.2 169 20.8 12 1.5 813 Whanganui 1,524 72.9 567 27.1 37 1.8 2,091 Capital and Coast 1,273 68.0 598 32.0 24 1.3 1,871 Hutt Valley 2,216 64.6 1,213 35.4 32 0.9 3,429 Wairarapa 329 69.7 143 30.3 4 0.8 472 Nelson Marlborough 689 46.7 786 53.3 14 0.9 1,475 West Coast 268 72.6 101 27.4 3 0.8 369 Canterbury 4,013 67.6 1,925 32.4 77 1.3 5,938 South Canterbury 314 48.3 336 51.7 3 0.5 650 Southern 2,091 63.7 1,193 36.3 53 1.6 3,284 Not recorded 248 59.0 172 41.0 5 1.2 420 Total 38,584 65.6 20,274 34.4 740 1.3 58,858 Newborn Metabolic Screening Programme 13
Figure 5 shows the percentage of samples received by the screening laboratory within four days or less from the date of sample taking. No DHB met the standard of 95% received within four days. Figure 5 Percentage of samples received by the laboratory in four days or less, January to December 2014 Newborn Metabolic Screening Programme 14
Indicator 5: Laboratory testing timeframes Table 9 identifies the percentage of samples that met the specified laboratory testing standard. The standard requires that 100% of samples meet the specified laboratory turnaround times. The range was 98.7% to 100%. Delays in results for amino acid disorders and fatty acid oxidation disorders were due to instrument breakdowns as without a backup instrument analyses either wait for repair or for tests to be done by the New South Wales screening laboratory in Sydney. Delays in cystic fibrosis screening were due to delayed mutation analysis results. Table 9 Percentage of results available within specified timeframes, by disorder, January to December 2014 Disorder Standard for turnaround time (days) Number met standard % met standard Congenital adrenal hyperplasia 2 58,516 99.3 Galactosaemia 2 58,927 100 Amino acid disorders 2 58,198 98.7 Fatty acid oxidation disorders 2 58,198 98.7 Biotinidase deficiency 5 58,944 100 Cystic fibrosis 5 58,344 99.0 Congenital hypothyroidism 5 58,547 99.3 (n= 58,870 samples) Newborn Metabolic Screening Programme 15
Indicator 6: Timeliness of reporting notification of screen positives The NMSP relies on early detection and treatment. This ensures babies with congenital metabolic disorders have their development potential impacted as little as possible from the disorder. The standard for this indicator is that 100% of babies with positive results are notified to their LMC or referring practitioner by the timeframe specified for each disorder. Most screening tests have a two-tier reporting system. Where results are highly likely to indicate the disorder is present, the results are telephoned to the LMC and referral made to an appropriate subspecialist paediatrician. All results in this category were reported inside the timeframes as shown in Table 11. Marginal test results are reported by mail, and in this case the written report is not generated until all the screening test results are available. The results will be phoned if there is a clinical reason to do so. Table 10 Percentage of positive test results reported within specified timeframes, by disorder, January to December 2014 Reason for report Standard: Calendar days (from receipt in laboratory to report) Number of positive test reports Number met timeframe % met timeframe Amino acid disorders 3 205 113 55.1 Fatty acid oxidation disorders 3 99 57 57.6 Congenital adrenal 3 hyperplasia 50 39 78.0 Galactosaemia 3 0 0 N/A Congenital 4 hypothyroidism 58 48 82.8 Biotinidase deficiency 9 0 0 N/A Cystic fibrosis 12 57 30 52.6 Of the reports which did not meet the turnaround time, the reasons include: waiting for cystic fibrosis gene testing or biotinidase deficiency screening results (all the delayed cystic fibrosis screen reporting was due to delayed gene results) waiting for amino acid and fatty acid oxidation screening results delayed due to breakdowns in the tandem mass spectrometer delay in sign-out one positive cystic fibrosis test was notified after 36 days due to a laboratory error. Newborn Metabolic Screening Programme 16
Table 11 outlines the percentage of urgent clinical critical positive results reported by timeframes and disorder. It is noted that the testing turnaround times are specified in working days but reported in calendar days. For example congenital adrenal hyperplasia (CAH) is two days for test result being available and three days for reporting. A sample which arrives on Friday and has a test result available and reported on Monday meets the testing timeframe but not the reporting timeframe. Table 11 Percentage of urgent clinical critical positive results reported within specified timeframes, by disorder, January to December 2014 Reason for report Amino acid disorders Fatty acid oxidation disorders Congenital adrenal hyperplasia Standard: Calendar days (from receipt in laboratory to report) Number of urgent critical positive test reports Number met timeframe % met timeframe 3 4 4 100 3 8 7 88* 3 4 4 100 Galactosaemia 3 0 0 N/A Congenital hypothyroidism Biotinidase deficiency 4 17 16 94* 9 0 0 N/A Cystic fibrosis 12 0 0 N/A *Outlier at 5d (sample received 24/12/14). Outlier at 5d. Newborn Metabolic Screening Programme 17
Indicator 7: Collection and receipt of second samples Second samples are requested when samples are not suitable for testing or there are minor elevations of screened metabolites. Table 12 outlines the follow-up of second samples requested by the screening laboratory by DHB. No DHB met the standard of 100% of second samples received by the laboratory, or declined, within ten calendar days of the request. The national average is 38.2%. Improvements compared to 2013 have been made by the NMSP working closely with LMCs to ensure follow-up is completed before the baby is discharged from midwifery care at 4 to 6 weeks of age. Table 12 Follow-up of requested second samples by DHB, January to December 2014 DHB region Less than or equal to 10 days Other follow up No follow up Follow up complete Total samples No. % No. % No. % No. % No. Northland 18 32.1 36 64.3 2 3.6 54 96.4 56 Waitemata 88 48.4 92 50.5 2 1.1 180 98.9 182 Auckland 57 49.1 57 49.1 2 1.7 114 98.3 116 Counties Manukau 80 31.9 162 64.5 9 3.6 242 96.4 251 Waikato 44 38.3 70 60.9 1 0.9 114 99.1 115 Lakes 19 42.2 22 48.9 4 8.9 41 91.1 45 Bay of Plenty 22 43.1 27 52.9 2 3.9 49 96.1 51 Tairawhiti 5 27.8 13 72.2 0 0.0 18 100.0 18 Taranaki 12 34.3 22 62.9 1 2.9 34 97.1 35 Hawkes Bay 17 37.0 28 60.9 1 2.2 45 97.8 46 Whanganui 14 60.9 9 39.1 0 0.0 23 100.0 23 Mid Central 22 37.3 37 62.7 0 0.0 59 100.0 59 Hutt Valley 16 35.6 29 64.4 0 0.0 45 100.0 45 Capital and Coast 30 40.0 39 52.0 6 8.0 69 92.0 75 Wairarapa 1 14.3 6 85.7 0 0.0 7 100.0 7 Nelson 10 31.3 22 68.8 0 0.0 32 100.0 32 Marlborough West Coast 0 0.0 4 100.0 0 0.0 4 100.0 4 Canterbury 34 32.1 67 63.2 5 4.7 101 95.3 106 South Canterbury 1 12.5 7 87.5 0 0.0 8 100.0 8 Southern 23 37.1 39 62.9 0 0.0 62 100.0 62 Not recorded 4 25.0 12 75.0 0 0.0 16 100.0 16 Total 517 38.2 800 59.2 35 2.6 1317 97.4 1352 Note: follow-ups are not counted in the total number of screens. Follow-up samples include those that were unsuitable for testing or were suspected of a disorder. Newborn Metabolic Screening Programme 18
Indicator 8: Diagnosis and commencement of treatment by disorder The NMSP relies on confirmed detection and timely treatment to ensure babies with congenital metabolic disorders have their development potential impacted as little as possible from the disorder. The standard is for 100% of babies who receive a screen positive result to be diagnosed and treatment commenced by the time specified for each disorder. The time to diagnosis and commencement of treatment is determined by the age of the baby when the specimen was collected, the transit time to the laboratory, the time to confirmation and reporting of test results and the time to make the diagnosis and commence treatment. The summarised numbers of detected cases of the screened disorders and the number treated by the specified age are given in Table 13. Table 13 Age at treatment, January to December 2014 Disorder Standard: Calendar days of age of baby at treatment commenced Number of cases Number treated by specified age Biotinidase deficiency 14 0 N/A Cystic fibrosis 28 16 2 Congenital hypothyroidism Congenital adrenal hyperplasia 10 31 12 10 2 2 Galactosaemia 10 0 N/A Amino acid disorders 10 2 0 Fatty acid oxidation disorders 10 9 8 Of the 16 babies diagnosed with cystic fibrosis, the NMSP has data on 12. Two were treated before 28 days, the others at 29-63 days. Screening had been declined for one baby and a test was ordered by the paediatrician investigating the baby s failure to thrive. The test was positive and the baby treated at 160 days. There were 10 cases of congenital hypothyroidism treated outside the timeframe as their initial levels of TSH were between 15 and 29 miu/l and notification was made following the results of Newborn Metabolic Screening Programme 19
a second sample. No data is available for five. The remaining four were treated at 11, 14, 15 and 16 days. The two patients with amino acid breakdown disorders both have PKU. One was treated at 11 days the other at 25 days (the sample took 20 days in transit). One patient with MCAD treated at 50 days (sample took 48 days in transit). Newborn Metabolic Screening Programme 20
Indicator 9: Blood spot card storage and return Where requested, blood spots are to be returned to parents/guardians/individuals by tracked courier within 28 days of the request. Of 671 requests for blood spot returns, 664 were returned within the timeframe. Five cards were not returned as they had insufficient information. This was requested but not provided. The remaining two samples were returned in 29 and 42 days after the original request but within a day or two of receiving either a second sample or complete information for the return. In general samples are returned very quickly with a median time over this period of 1 day. The NMSP Policy Framework 2011 lists possible secondary uses for residual screening samples (section 4.1(b)). Table 14 shows that 76 cards were used for the benefit of the individual and family/whanau. 67 of these were used to determine whether congenital cytomegalovirus was the cause of symptoms in the baby or child. The research study was to determine whether newborn screening for the fatty acid oxidation disorder VLCAD had missed any cases since the cut-off used in New Zealand is high relative to that in some other screening programmes; and whether these results could be due to a benign common mutation among some Pacific populations. Results are expected in 2015. Table 14 Reasons for secondary use of blood spot samples, January to December 2014 Secondary use Number Benefit of the individual and family/whanau 76 Forensic/police/coroner investigations 0 Mortality review 0 Research 150 Other 0 Total 226 Newborn Metabolic Screening Programme 21
Screening performance and incidence Follow-up of positive tests Follow-up of positive tests are detailed in Table 15. Appropriate follow-up may be: a specialist paediatrician visit a further dried blood sample a test done elsewhere notification that baby has died. Overall 436 babies were referred for paediatric examination or had a request for a second sample because of a positive screen result and 995 because of an unsuitable sample. Table 15 Newborn screening follow-up by condition, 2014 Condition Amino acid breakdown disorders Fatty acid oxidation disorders Number of positive tests Follow-up by scheduled NICU or requested sample (e.g. sample taken too early) Other follow-up (paediatric referral, second test) Number with appropriate follow-up % with appropriate follow-up 169 0 167 167 100 99 0 99 99 100 Biotinidase deficiency 3 1 0 1 100 Congenital adrenal hyperplasia Congenital hypothyroidism 50 0 47 47 94 58 8 50 58 100 Cystic fibrosis 57 0 57 57 100 Galactosaemia 0 0 0 0 N/A NB: A borderline result when a further sample is scheduled is no longer counted as a positive screen as the screening consists of more than one sample. Newborn Metabolic Screening Programme 22
Clinical utility Newborn screening is justified for conditions in which there is clinical benefit from diagnosis made earlier by screening than it would be made by clinical presentation and diagnosis. Screening audit forms contain a question about whether the diagnosis was suspected before the screening test result is available. Reasons for clinical detection are: family history (FH) meconium ileus. The numbers are given in Table 16. Table 16 Clinical utility of screening, 2014 Disorder Number of cases Diagnosis suspected before screen result Reason for suspicion Biotinidase deficiency 0 0 Cystic fibrosis 16 6 Congenital hypothyroidism Congenital adrenal hyperplasia 31 0 2 1 Galactosaemia 0 0 1 FH, 2 meconium ileus, 3 failure to thrive 1 ambiguous genitalia Amino acid disorders 2 0 Fatty acid oxidation disorders 9 1 1 FH Total conditions 60 8 Overall 60 cases of screened disorders were detected by the programme and in 52 of these there was no clinical suspicion of the disorder before the screening test result. Newborn Metabolic Screening Programme 23
Incidence of screened disorders Amino acid breakdown disorders Since screening started in 2006, 564,525 infants have been screened and 62 cases detected, giving an incidence of 1:9,100. This includes PKU and MSUD. PKU There were two cases of PKU found in 2014. Since screening started in 1969 2,643,258 infants have been screened for PKU and 123 cases found, none notified missed, to give an incidence of 1:21,500. Benign hyperphenylalaninemia is not counted in this figure. It is problematic comparing PKU incidence as the definition of the disorder is a level of phenylalanine that requires treatment and the level has varied time to time. MSUD No cases of MSUD were found in 2014. Since screening started in 1969, 2,643,258 infants have been screened for MSUD, ten classical cases found; none were notified missed, giving an incidence of 1:264,000. Biotinidase deficiency Since screening started in 1986, 1,709.964 infants have been screened and eight cases detected giving an incidence of 1:214,000. Congenital adrenal hyperplasia Since screening started in 1986, 1,756,913 infants have been screened and 75 cases detected giving an incidence of 1:23,400. Congenital hypothyroidism Since screening started in 1981, 1,977,329 infants have been screened and 539 cases detected giving an incidence of 1:3668. There is a trend to an increasing incidence of congenital hypothyroidism in New Zealand. The increase is in dyshormonogenesis. This condition is more common in people of Asian and Pacific origin and the increase coincides with an increase in Asian births as immigration changes the New Zealand demographic. Cystic fibrosis Since screening started in 1983, 2,692,545 infants have been screened and 400 cases detected giving an incidence of 1:6,700. There were 58,673 babies screened in 2014 (of whom approximately 46% were of European ethnicity) and 15 cases of CF detected. This gives an incidence in the European births of 1:1,800. Fatty acid oxidation disorders Since screening started in 2006, 564,525 infants have been screened and 70 cases detected giving an incidence of 1:.8,100. Galactosaemia Since screening started in 1973, 2, 515,353 infants have been screened and 24 cases detected giving an incidence of 1:105,000. Newborn Metabolic Screening Programme 24
Appendix 1: NMSP National Indicators 1: NEWBORN METABOLIC SCREENING COVERAGE DESCRIPTION The proportion of babies who have had newborn metabolic screening. RATIONALE All babies whose parents/guardians consent to screening should have screening. RELEVANT OUTCOME All babies whose parents/guardians consent to newborn metabolic screening are screened. STANDARD 100% of babies whose parents/guardians consent to screening are screened. METHODOLOGY Indicator 1.1 Numerator: Denominator: Number of babies screened. Number of live births. NOTES Denominator limitations to be explained in published reports Reporting by: DHB Ethnicity Deprivation status Newborn Metabolic Screening Programme 25
2: TIMING OF SAMPLE TAKING DESCRIPTION 1. The proportion of eligible babies who have a newborn metabolic screening sample taken. 2. The proportion of eligible babies who have a newborn metabolic screening sample taken between 48 and 72 hours of birth. RATIONALE Timely sample collection leads to the best possible chance of a baby receiving early diagnosis and treatment where necessary. Severe forms of some of the disorders screened for can be fatal within seven to ten days. Many may not show any signs or symptoms of disease until irreversible damage has occurred. However, the baby must have been independent of their mother long enough for their indicator biochemicals to show an abnormality. Therefore the optimum window for sample collection is between 48 and 72 hours of birth. RELEVANT OUTCOME Babies screened should have a newborn metabolic screening sample taken between 48 and 72 hours of birth. STANDARD 95% of first samples are taken between 48 and 72 hours of birth. METHODOLOGY Indicator 2 Numerator: Denominator: Number of babies who have a newborn metabolic screening sample taken between 48 and 72 hours of birth. (see data limitations above, the measure used in this report is the number of babies screened at 2 days) Number of babies who have a newborn metabolic screening sample taken. NOTES Samples for screening must be taken in accordance with Programme Guidelines and Policy and Quality requirements. Reporting by: DHB Ethnicity Deprivation status Newborn Metabolic Screening Programme 26
3: QUALITY OF BLOOD SAMPLES DESCRIPTION The quality of the blood spot sample. RATIONALE Accurate testing of blood spot samples is reliant on the quality of the sample. Unsatisfactory samples require a repeat sample which could have been avoided. RELEVANT OUTCOME Blood spot samples are of sufficient quality for laboratory testing for screened disorders. STANDARD 99% of blood spot samples are of satisfactory quality. METHODOLOGY Indicator 3 Numerator: Denominator: Number of samples of satisfactory quality as reported by the laboratory. Number of samples taken. NOTES Requirements for a satisfactory sample are detailed in Chapter 7, page 21-22 of Programme Guidelines. Reporting by DHB Newborn Metabolic Screening Programme 27
4: SAMPLE DISPATCH AND DELIVERY DESCRIPTION The time taken for the sample to be received by the laboratory after being taken. RATIONALE The NMSP relies on timeliness. Samples must be sent to the laboratory as soon as they are dry. Samples must be received by the laboratory as soon as possible after they are taken. RELEVANT OUTCOME Samples are received by the laboratory within four days of being taken. STANDARD 95% of samples are received by the laboratory within four calendar days of being taken. METHODOLOGY Indicator 4 Numerator: Denominator: Number of samples received by laboratory within four calendar days of being taken. Number of samples received by laboratory. NOTES Requirements for sending samples to the laboratory are detailed in Chapter 7, page 23 of Programme Guidelines Reporting by DHB Newborn Metabolic Screening Programme 28
5: LABORATORY TESTING TIMEFRAMES DESCRIPTION The time taken by the laboratory to test each sample for each of the specified disorders (turnaround time). RATIONALE Samples should be tested as soon as possible to ensure that screen positives can be acted on as quickly as possible to reduce / minimise avoidable harm. RELEVANT OUTCOMES All samples are tested within the specified timeframes. Samples received before 07:30am are tested the same day. STANDARD 100% of samples meet the following laboratory turnaround times: Disorder Working days (from receipt by laboratory) Congenital adrenal hyperplasia 2 Galactosaemia 2 Amino acid disorders 2 Fatty acid oxidation disorders 2 Biotinidase deficiency 5 Cystic fibrosis 5 Congenital hypothyrodism 5 METHODOLOGY Indicator 5 Numerator: Denominator: Number of samples tested and reported within specified timeframes. Number of samples tested. Newborn Metabolic Screening Programme 29
6: TIMELINESS OF REPORTING NOTIFICATION OF SCREEN POSITIVES DESCRIPTION The time taken for a baby with a positive screening result to be referred for diagnostic testing. RATIONALE The NMSP relies on early detection and treatment. This ensures babies with congenital metabolic disorders have their development potential impacted as little as possible from the disorder. RELEVANT OUTCOME All babies with positive screening results are referred for further testing within the specified timeframes after results become available. STANDARD 100% of babies with positive results are notified to their LMC / referring practitioner by the laboratory within the following timeframes: Reason for report Calendar days (from receipt in lab test result) Amino acid disorders 3 Fatty acid oxidation disorders 3 CAH 3 Galactosaemia 3 CH 4 Biotinidase deficiency 9 Cystic fibrosis 12 METHODOLOGY Indicator 6 Numerator: Denominator: Number of babies who are notified to their referrer for further testing for a particular disorder within the number of calendar days specified for that disorder. Number of babies who receive a positive screening result for a particular disorder. Newborn Metabolic Screening Programme 30
7: COLLECTION AND RECEIPT OF SECOND SAMPLES DESCRIPTION The number of babies that have had second samples taken, sent, and received by the laboratory. Note: this indicator does not cover highly positive samples. It is for those around the cut off who have letters sent to them. RATIONALE If a second sample is required it means that a baby has not been fully screened, or that his/her results were borderline. Second samples should be taken as soon as possible so that the baby can be treated early if he/she has a disorder. RELEVANT OUTCOME Second samples are taken, sent, and received by the laboratory as soon as possible. STANDARD 100% of second samples are received by the laboratory, or declined, within ten calendar days of request. METHODOLOGY Indicator 7.1 Numerator: Total number of second samples collected, declined, or baby died. Denominator: Indicator 7.2 Number of second samples requested. Numerator: Number of second samples received within ten calendar days. Denominator: Total number of second samples received and declined. NOTES Requirements for repeat samples are detailed in Chapter 7, page 24-25 of Programme Guidelines. Reporting by DHB Newborn Metabolic Screening Programme 31
8 DIAGNOSIS AND COMMENCEMENT OF TREATMENT BY DISORDER DESCRIPTION The number of babies with a positive screening result who receive a confirmed diagnosis and timely commencement of treatment. RATIONALE The NMSP relies on confirmed detection and timely treatment to ensure babies with congenital metabolic disorders have their development potential impacted as little as possible from the disorder. RELEVANT OUTCOME All babies with a metabolic disorder and a screen positive result receive a confirmed diagnosis and timely commencement of treatment. STANDARD 100% of babies who receive a screen positive result are diagnosed and commence treatment by: Disorder Calendar days Biotinidase deficiency 14 Cystic fibrosis 28 CH 10 CAH 10 Galactosaemia 10 Amino acid disorders 10 Fatty acid oxidation disorders 10 METHODOLOGY Indicator 8 Numerator: Denominator: NOTES Number of babies who are diagnosed and commence treatment within the timeframes specified. Number of babies who receive a screen positive result and are diagnosed with and treated for a metabolic disorder. Clinically-diagnosed babies will be reported separately. Measurement may also be by case review or periodic audit / evaluation. Newborn Metabolic Screening Programme 32
9: CARD STORAGE AND RETURN DESCRIPTION The time taken for the laboratory to return requested blood spot cards to parents/guardians/individuals. RATIONALE Where requested blood spot cards should be returned within: 28 days of completion of screening 28 days of valid (fully completed) request for return. RELEVANT OUTCOME All blood spot cards are returned to parents/guardians/individuals by tracked courier within 28 days. STANDARD 1. Where requested, 100% of blood spot cards are returned to parents/guardians within 28 days of completion of screening. 2. 100% of blood spot cards are returned to the authorised person by tracked courier within 28 calendar days of valid request. METHODOLOGY Indicator 9 Numerator: Number of blood spot cards returned within 28 days. Denominator: Number of blood spot cards requested by parents/guardians/individuals. NOTES Complete information is required by the laboratory in order to process requests for return of blood spot cards, as per Programme Guidelines in Chapter 11. Newborn Metabolic Screening Programme 33